A sensitive and high-throughput LC-MS/MS method for the quantification of pegylated-interferon-α2a in human serum using monolithic C18 solid phase extraction for enrichment

The analysis of pegylated-interferon-alpha(2a) in patient serum samples is of high interest for clinic research trials, as this therapeutic protein has become an important antiviral treatment. In this Study, an LC-MS/MS method for the absolute quantification of pegylated-interferon-alpha(2a) in human serum was developed. The assay achieved a lower limit of quantification of 3.6 ng/mL (60 pM) with the use of a monolithic C(18) solid phase extraction to enrich the target protein. The linear range of the assay was defined up to 54 ng/mL to measure the typical clinical pegylated-interferon-alpha(2a) levels, and within this range, the precision and accuracy were found to be within +/- 20%. The method was applied to a clinical study and found suitable for high-throughput analysis of pegylated-interferon-alpha(2a) in human serum. In addition, further investigations suggested the enrichment step may have general application to the sensitive analysis of other low molecular weight proteins. (C) 2009 Elsevier B.V. All rights reserved.